Oil Pump Upgrade question--2.7 with bearing issues.

moneymanager · 08-16-2013, 10:05 AM

We recently pulled my 2.7 motor apart, having observed larger than normal aluminum flakes in the filter, reduced oil pressure and increased lead content in the oil over a period of months. Motor had 30k miles including 100 track hours. Inspection showed everything perfect except rods and mains at front (clutch end) of case which were worn and require redo. When built, case was blueprinted, line bored and shuffle pinned. Compression is modest at 9.5. The oil bypass modification was done but the pump was stock 1975.
I know track hours are demanding but I expected a bit more mileage than I got. I'm guessing that the bearings failed because they are the farthest from the oil pump and that a pump upgrade to Carrera or 964 specs would be prudent. I'd welcome comments/suggestions.

Flat6pac · 08-16-2013, 02:10 PM

If you upgrade to the 4 rib pump, 4 ribs in the middle of the back side, that is the same pump used for the 77 and later engines through 89 although the 3.2 suffers from lack of oil on rods 2 and 5 at times.
Bruce

moneymanager · 08-21-2013, 04:33 PM

Consensus seems to be that the bearing failure was NOT an oil flow problem but something else. I'm going to the 4rib pump anyway; we're still trying to decide what, if anything, else needs attention. No one has seen this?

stownsen914 · 08-21-2013, 04:38 PM

What kind of oil temps do you see? 2.7 cars were notorious for being under-cooled and ran 250+ oF on the track. That could shorten your engine life for sure ...

Scott

moneymanager · 08-21-2013, 04:40 PM

Thanks for your interest. I've never been over 220°, and that would be very unusual. I have plenty of cooling.

stownsen914 · 08-22-2013, 10:26 AM

Quote:

Originally Posted by moneymanager

Thanks for your interest. I've never been over 220°, and that would be very unusual. I have plenty of cooling.

OK, well that seems very reasonable. 100 hours + 30K miles does seem a bit on the short end of reasonable for engine life. A couple other things that come to mind as potential factors:
- What engine oil do you use? And changed regularly, especially after track days?
- Has the engine experienced any "hardships" like overrevs, etc?

moneymanager · 08-22-2013, 11:40 AM

Used Mobil One in early days, Brad Penn lately. It is changed roughly every other event.
So far as I know, no over revving.
There was one odd event about a year ago... a few (10-20) bigger than normal flakes of aluminum showed up in the oil filter. In fact I expected to see something somewhere in the motor when we took it apart which might have been the source. We found nothing. This led us to believe that something might have somehow gotten in the crankcase and somehow been pulled thru the oil system. But if it did, why were the only bearings affected at the front?

KTL · 08-22-2013, 01:57 PM

Crank main bearings at the #1 end bearing actually are not farthest from the pump. They're the closest.

The #2 cyl and #5 cyl rod bearings are farthest from the pump because the rod journals are fed from the ends inward. That's the reasoning behind the typical cross-drilling routine which gets the feed coming from the #4 main location (middle) by grooving the bearing (or the main journal) and enlarge the #4 main bearing feed hole in both the case and bearing shell.

I've always been under the impression that bearing damage at the flywheel end can be partly attributed to the shock loading of the clutch, especially with hard use like track/racing where there's quick & abrupt clutch action. But I recently observed some of the fellas saying that #1 bearing with issues indicates a line bore problem.

What do these bearings say?

Steve@Rennsport · 08-22-2013, 04:24 PM

Engine forensics is everything and no detail can be assumed or overlooked. Failure to do so results in "encore" performances (which gets very expensive).

Aluminum comes from either intermediate shaft gears or pistons and deserves a very close & detailed inspection of such engine components.

Engine bearings can tell you many things including contamination issues (#1 & # 7 mains & rods) and/or lubrication issues (#2 & #5 rod bearings). Many people have trouble here due to inadequate cleaning of the entire system.

Wear patterns tell you about bearing saddle alignment, or lack of it.

The Devil is in the details,....

KTL · 08-23-2013, 09:36 AM

Encore...... I hear you Dr. Steve! My last failure was an ugly one. Don't want to repeat that.

ENTIRE oil system has been scrubbed leaving nothing, absolutely nothing, to chance

Engine case- all gallery plugs removed, clean bores, new plugs
Ext. t-stat disassembled, new regulator
Internal t-stat gets new regulator too
Piston squirters- new. No way i'm risking leaving those in there.
Oil pump- new (used 964 pump disassembled for inspection) because pump interior was thrashed by bearing debris
I-shaft flushed and closely inspected
All new bearings, even spendy #8. All destroyed (except I-shaft, which is ironic...) by oil starvation.
New chains & ramps. Why? Chain sprockets mush bearing material into chain links and no way to clean it out. Ramps do a fine job of hiding bearing debris where you can't reach it. Cheap insurance to replace the inexpensive ramps.
Solid chain tensioners, so no worries of contamination there....
ALL oil lines manually scrubbed or replaced (mostly replaced due to being old braided stainless hose throughout car).
Both oil coolers shelved, new front center cooler purchased. Likely will not ultrasonic clean and pass off the old coolers to someone else, risking their engine.
Factory oil tank shelved, new Peterson front mount tank. Will ultrasonic clean in future.
Cam housings junked due to impractical cost to repair bore damage. New used 965 housings completely disassembled, cleaned
New pistons, pins, rings because piston skirts were destroyed by bearing debris
Good used cyls were sourced since cyls were also scored by bearing debris and required re-plating.
Crankshaft shelved, sourced a good used STD/STD crank. Every journal on crank was scored.
Pauter rods rebuilt, again, one (#5, surprise surprise) did not survive the battle
Cam bearings repaired. These were previously new hardwelds
Affected rockers (5) repaired/reground
Heads FULLY disassembled & cleaned, one required replacement

Like I said, UGLY.

Point of listing that is not to boast how thorough I am or impress you with how much money I wasted. Point is to show how much stuff is affected when you have a major bearing failure due to oiling problem. All that bearing material gets distributed to all of the above stuff, causing a lot of damage.

So you have all that work to repair or replace parts, along with lots and lots of cleaning to ensure none of that material still hides somewhere, waiting to cause more damage when the engine gets going again. Moral of the story is that even a mild, isolated bearing failure should not be treated lightly. Never know where that stuff is hiding in the system. Gotta suck it up and clean everything. Because you just don't know what part will get damaged by that rogue debris.

Needless to say my wall of shame has quite a few parts on it now....

1-ev.com · 1-ev.com's Garage

WoW

Guess changing oil early then described it the manual WILL cost less, I've seen some people say "$250 for oil change a rip-off"

I do oil change on my SUV 1/2 live what it said in the book...

Thank you Kevin for sharing this info, it is TRULY priceless

Quote:

Originally Posted by KTL

Encore...... I hear you Dr. Steve! My last failure was an ugly one. Don't want to repeat that.

ENTIRE oil system has been scrubbed leaving nothing, absolutely nothing, to chance

Engine case- all gallery plugs removed, clean bores, new plugs
Ext. t-stat disassembled, new regulator
Internal t-stat gets new regulator too
Piston squirters- new. No way i'm risking leaving those in there.
Oil pump- new (used 964 pump disassembled for inspection) because pump interior was thrashed by bearing debris
I-shaft flushed and closely inspected
All new bearings, even spendy #8. All destroyed (except I-shaft, which is ironic...) by oil starvation.
New chains & ramps. Why? Chain sprockets mush bearing material into chain links and no way to clean it out. Ramps do a fine job of hiding bearing debris where you can't reach it. Cheap insurance to replace the inexpensive ramps.
Solid chain tensioners, so no worries of contamination there....
ALL oil lines manually scrubbed or replaced (mostly replaced due to being old braided stainless hose throughout car).
Both oil coolers shelved, new front center cooler purchased. Likely will not ultrasonic clean and pass off the old coolers to someone else, risking their engine.
Factory oil tank shelved, new Peterson front mount tank. Will ultrasonic clean in future.
Cam housings junked due to impractical cost to repair bore damage. New used 965 housings completely disassembled, cleaned
New pistons, pins, rings because piston skirts were destroyed by bearing debris
Good used cyls were sourced since cyls were also scored by bearing debris and required re-plating.
Crankshaft shelved, sourced a good used STD/STD crank. Every journal on crank was scored.
Pauter rods rebuilt, again, one (#5, surprise surprise) did not survive the battle
Cam bearings repaired. These were previously new hardwelds
Affected rockers (5) repaired/reground
Heads FULLY disassembled & cleaned, one required replacement

Like I said, UGLY.

Point of listing that is not to boast how thorough I am or impress you with how much money I wasted. Point is to show how much stuff is affected when you have a major bearing failure due to oiling problem. All that bearing material gets distributed to all of the above stuff, causing a lot of damage.

So you have all that work to repair or replace parts, along with lots and lots of cleaning to ensure none of that material still hides somewhere, waiting to cause more damage when the engine gets going again. Moral of the story is that even a mild, isolated bearing failure should not be treated lightly. Never know where that stuff is hiding in the system. Gotta suck it up and clean everything. Because you just don't know what part will get damaged by that rogue debris.

Needless to say my wall of shame has quite a few parts on it now....

Steve@Rennsport · 08-23-2013, 11:03 AM

Well done, Kevin,.....

KTL · 08-23-2013, 02:16 PM

Quote:

Originally Posted by Steve@Rennsport

Well done, Kevin,.....

Indeed. I wasted that engine real good.

Most would say, are you crazy? Why didn't you just buy a good used engine. "Because used engines are like a box of chocolates?" Oh shut up Forrest......

Because it just didn't make good sense to me to start off a mild race engine build with an engine of unknown history that I would rebuild anyway:

My case checks out good & has fresh head studs
My Pauter rods are being reconditioned, i.e. would probably go cheap out & rebuild stock rods w/ARP bolts in the used engine
Good used crank getting reconditioned
All new bearings are a must-do IMO on a used engine build
I have good twin plugged heads, whereas heads would likely need service on used engine

and so on...... See how the numbers don't add up to start with a used one?